packet lib: Add packet library of Geneve

Signed-off-by: Shinpei Muraoka <shinpei.muraoka@gmail.com>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>

4 files changed, 196 insertions, 0 deletions

diff --git a/doc/source/library_packet_ref.rst b/doc/source/library_packet_ref.rst
index 29c68a20..56c09f9f 100644
--- a/doc/source/library_packet_ref.rst
+++ b/doc/source/library_packet_ref.rst
@@ -56,6 +56,9 @@ Protocol Header classes
 .. automodule:: ryu.lib.packet.vxlan
    :members:
 
+.. automodule:: ryu.lib.packet.geneve
+   :members:
+
 .. automodule:: ryu.lib.packet.gre
    :members:
 
diff --git a/ryu/lib/packet/ether_types.py b/ryu/lib/packet/ether_types.py
index bfa78995..e8287d3b 100644
--- a/ryu/lib/packet/ether_types.py
+++ b/ryu/lib/packet/ether_types.py
@@ -16,6 +16,7 @@
 
 ETH_TYPE_IP = 0x0800
 ETH_TYPE_ARP = 0x0806
+ETH_TYPE_TEB = 0x6558
 ETH_TYPE_8021Q = 0x8100
 ETH_TYPE_IPV6 = 0x86dd
 ETH_TYPE_SLOW = 0x8809
diff --git a/ryu/lib/packet/geneve.py b/ryu/lib/packet/geneve.py
new file mode 100644
index 00000000..6cbba495
--- /dev/null
+++ b/ryu/lib/packet/geneve.py
@@ -0,0 +1,189 @@
+# Copyright (C) 2016 Nippon Telegraph and Telephone Corporation.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+# implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""
+Geneve packet parser/serializer
+"""
+
+import struct
+
+from ryu.lib import stringify
+from ryu.lib import type_desc
+from . import packet_base
+from . import ether_types
+
+
+UDP_DST_PORT = 6081
+
+
+class geneve(packet_base.PacketBase):
+    """Geneve (RFC draft-ietf-nvo3-geneve-03) header encoder/decoder class.
+
+    An instance has the following attributes at least.
+    Most of them are same to the on-wire counterparts but in host byte order.
+    __init__ takes the corresponding args in this order.
+
+    ============== ========================================================
+    Attribute      Description
+    ============== ========================================================
+    version        Version.
+    opt_len        The length of the options fields.
+    flags          Flag field for OAM packet and Critical options present.
+    protocol       Protocol Type field.
+                   The Protocol Type is defined as "ETHER TYPES".
+    vni            Identifier for unique element of virtual network.
+    options        List of ``Option*`` instance.
+    ============== ========================================================
+    """
+    _HEADER_FMT = "!BBHI"
+    _MIN_LEN = struct.calcsize(_HEADER_FMT)
+
+    #  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+    # +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+    # |Ver|  Opt Len  |O|C|    Rsvd.  |          Protocol Type        |
+    # +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+    # |        Virtual Network Identifier (VNI)       |    Reserved   |
+    # +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+    # |                    Variable Length Options                    |
+    # +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+
+    # Flags
+    OAM_PACKET_FLAG = 1 << 7
+    CRITICAL_OPTIONS_FLAG = 1 << 6
+
+    def __init__(self, version=0, opt_len=0, flags=0,
+                 protocol=ether_types.ETH_TYPE_TEB, vni=None, options=None):
+        super(geneve, self).__init__()
+
+        self.version = version
+        self.opt_len = opt_len
+        assert (flags & 0x3F) == 0
+        self.flags = flags
+        self.protocol = protocol
+        self.vni = vni
+        for o in options:
+            assert isinstance(o, Option)
+        self.options = options
+
+    @classmethod
+    def parser(cls, buf):
+        (ver_opt_len, flags, protocol,
+         vni) = struct.unpack_from(cls._HEADER_FMT, buf)
+        version = ver_opt_len >> 6
+        # The Opt Len field expressed in four byte multiples.
+        opt_len = (ver_opt_len & 0x3F) * 4
+
+        opt_bin = buf[cls._MIN_LEN:cls._MIN_LEN + opt_len]
+        options = []
+        while opt_bin:
+            option, opt_bin = Option.parser(opt_bin)
+            options.append(option)
+
+        msg = cls(version, opt_len, flags, protocol, vni >> 8, options)
+
+        from . import ethernet
+        geneve._TYPES = ethernet.ethernet._TYPES
+        geneve.register_packet_type(ethernet.ethernet,
+                                    ether_types.ETH_TYPE_TEB)
+
+        return (msg, geneve.get_packet_type(protocol),
+                buf[cls._MIN_LEN + opt_len:])
+
+    def serialize(self, payload=None, prev=None):
+        tunnel_options = bytearray()
+        for o in self.options:
+            tunnel_options += o.serialize()
+        self.opt_len = len(tunnel_options)
+        # The Opt Len field expressed in four byte multiples.
+        opt_len = self.opt_len // 4
+
+        return (struct.pack(self._HEADER_FMT,
+                            (self.version << 6) | opt_len,
+                            self.flags, self.protocol, self.vni << 8)
+                + tunnel_options)
+
+
+class Option(stringify.StringifyMixin, type_desc.TypeDisp):
+    """
+    Tunnel Options
+    """
+    _OPTION_PACK_STR = "!HBB"
+    _OPTION_LEN = struct.calcsize(_OPTION_PACK_STR)
+
+    #  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+    # +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+    # |          Option Class         |      Type     |R|R|R| Length  |
+    # +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+    # |                      Variable Option Data                     |
+    # +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+    def __init__(self, option_class=None, type_=None, length=0):
+        super(Option, self).__init__()
+        if option_class is None or type_ is None:
+            (option_class, type_) = self._rev_lookup_type(self.__class__)
+        self.option_class = option_class
+        self.type = type_
+        self.length = length
+
+    @classmethod
+    def parse_value(cls, buf):
+        # Sub-classes should override this method, if needed.
+        return {}
+
+    def serialize_value(self):
+        # Sub-classes should override this method, if needed.
+        return b''
+
+    @classmethod
+    def parser(cls, buf):
+        (option_class, type_,
+         length) = struct.unpack_from(cls._OPTION_PACK_STR, buf)
+
+        # The Length field expressed in four byte multiples.
+        length *= 4
+        subcls = Option._lookup_type((option_class, type_))
+
+        return (
+            subcls(option_class=option_class, type_=type_, length=length,
+                   **subcls.parse_value(
+                       buf[cls._OPTION_LEN:cls._OPTION_LEN + length])),
+            buf[cls._OPTION_LEN + length:])
+
+    def serialize(self, _payload=None, _prev=None):
+        data = self.serialize_value()
+        self.length = len(data)
+        # The Length field expressed in four byte multiples.
+        length = self.length // 4
+
+        return (struct.pack(self._OPTION_PACK_STR, int(self.option_class),
+                            self.type, length) + data)
+
+
+@Option.register_unknown_type()
+class OptionDataUnknown(Option):
+    """
+    Unknown Option Class and Type specific Option
+    """
+    def __init__(self, buf, option_class=None, type_=None, length=0):
+        super(OptionDataUnknown, self).__init__(option_class=option_class,
+                                                type_=type_,
+                                                length=length)
+        self.buf = buf
+
+    @classmethod
+    def parse_value(cls, buf):
+        return {"buf": buf}
+
+    def serialize_value(self):
+        return self.buf
diff --git a/ryu/lib/packet/udp.py b/ryu/lib/packet/udp.py
index f39fb901..9d3ed3c5 100644
--- a/ryu/lib/packet/udp.py
+++ b/ryu/lib/packet/udp.py
@@ -19,6 +19,7 @@ from . import packet_base
 from . import packet_utils
 from . import dhcp
 from . import vxlan
+from . import geneve
 
 
 class udp(packet_base.PacketBase):
@@ -60,6 +61,8 @@ class udp(packet_base.PacketBase):
         if (dst_port == vxlan.UDP_DST_PORT or
                 dst_port == vxlan.UDP_DST_PORT_OLD):
             return vxlan.vxlan
+        if dst_port == geneve.UDP_DST_PORT:
+            return geneve.geneve
         return None
 
     @classmethod